Demountable shelter



Feb. 10, 1953 c. D. WILLSON DEMOUNTABLE SHELTER 2 SHEETS4-SHEET 1 Filed Sept. 16, 1946 Feb. 10, 1953 c. D. WILLSON DEMOUNTABLE SHELTER Filed Sept. 16; 1946 2 SHEETS-SHEET 2 \\\\\\\A\\\\ QM Patented Feb. 10, 1953 UNITED STATES PATENT OFFICE DEMOUNTABLE SHELTER Corwin D. Willson, Flint, Mich.

Application September 16, 1946, Serial No. 697,254

7 Claims. (01. 189-36) This invention relates to improvements in shelter, such as for the military: insulated shelter that is well ventilated, compactly portable, quickly erected, easily demounted and adequate for use either in the arctic or tropics; and, more particularly, to shelter having improved covering and stiffening and joining elements.

Many of the novel features of the present invention are illustrated and described but were elected not to be claimed in my co-pending application Serial No. 403,059, filed July 18, 1941. The present invention, accordingly, is a continuation in part of my co-pending application now matured into Patent No. 2,427,937, issued September 23, 1947, hereafter called "parent patent.

Differences between the structures claimed in the parent patent and the structures to be claimed hereinafter are substantial. The parent patent concentrates on claims to the structure and manner of erection of a shelter having (1) a covering in sections of the unit wall type each com-prising a wall-thick insulative slab having, in most instances, a single adherent metal facing on the outside of the section and (2) a rib of butt-joined segments, each having a lengthwise slot opening on one side of the rib only, each rib segment being formed of a single metal strip rolled to have a slotted tube-like circular cross section and (3) a joint between covering and rib whereby the metal facing of the coveringsection is joined to the slot on one side (outside) of the rib only, while a batten on the opposite side (inside) of the rib hides the spaces between contiguous sections of the covering and the rib without achieving a real structural joint between them.

My present invention, on the other hand, primarily concerns a shelter having (1a) either a covering in sections of the double wall type or (11)) a covering in sections of the unit Wall type and (2) a rib having, in most instances, a lengthwise slot extending clear through opposite sides of the rib, the rib comprising two strips of metal each preformed to be curvilinear both lengthwise and crosswise of the strip before being laterally joined in spaced relation by intermittently spaced transverse fasteners, such as rivets, grommets and the like and (3) a joint wherein opposite facings of a unit wall section or inner and outer sections of a double wall are fastened to the same slot from opposite sides thereof.

Other important features differentiating the two inventions will become apparent as the description proceeds.

An important object of the invention is a shelter having a covering in sections and a stiffening frame in segments and fastening elements therebetween, one of said elements having a head to receive and a taper tip to transmit force bending the element lengthwise in a slot whereby one of said sections is joined to either side of one of said segments.

Another object of the invention is a well-ventilated shelter of the semi-circular cross section type and comprising parts compactly nestable for shipment, a shelter suited to use in the tropics even though having an outer facing of highly heat conductive material because of ventilators positioned in the curved sides and adjacent the floor of the shelter and other ventilators in the top and intermediate parts thereof, the ventilators being provided with suitable shields and/ or closures to keep out the rain.

Another object of the invention is a shelter having a loadbearing rib of firmly joined segments, each comprising two metal strips preformed to be curvilinear both crosswise and lengthwise before being laterally joined in spaced relation: the cross section of the rib being such that a covering in sheet form may be fastened thereto by force applied on fastening means having a driving head and taper tip and either a rigid or resilient cross section and entered into the rib from the side thereof.

Another object of the invention is a shelter having a rigid framework comprising both rectilinear and curvilinear ribs, each having a single slot extending from end to end and from side to side of the rib, the slot housing means whereby a fastener may be driven from either side of the rib into the slot to be caught and firmly held therewit'hin.

Another object of the invention is a shelter having inner and outer spaced coverings of semirigid sheets held in fixed relation by two laterally joined strips and by means driven into the side of and caught within a slot between said strips, said means having a driving head and taper tip and comprising either a laterally entered strip member or a nail, screw or the like.

These and other novel features and objects of the invention are hereinafter more fully described and claimed and the preferred form of the shelter and of the elements thereof is shown in the accompanying drawings, in which:

Fig. l is a plan of the shelter frame without its covering of sheet material.

Fig. 2 is a vertical section of the frame and shelter substructure taken on line 2-2 of Fig. 1.

Fig. 3 is an end view in elevation of the frame shown in Fig. 1.

Fig. 4 is a section transversely of four panels nested compactly for transport in a relatively flat bundle according to the invention.

Fig. 5 is a section taken on line 55 of Fig. 1.

Fig. 6 is a section of an alternate form of the rib shown in Fig. 5.

Fig. '1' is a section of another alternate form of the rib shown in Fig. 5.

Fig. 8 is an end in elevation of the completed structure after the frame shown in Fig. 3 has received the covering elements, opening closures, shields, etc.

Fig. 9 is an enlarged view of a bottom corner construction of the shelter.

Fig. 10 is a section of the type of structure covered by the parent patent, wherein the rib comprises but a single roller strip housing but a single slot and covering elements are fastened to but one side of the rib only.

Fig. 11 is a vertical section taken on line i I-l I of Fig. 3 through the butt-joint between a pair of butted segments after they have received across the joint parallel outer and inner covering sheets and means fastening the sheets to the frame.

Fig. 12 is a side view in perspective of the rib at the butt-joint of Fig. 11 with. the covering sheets and fastening strip members removed for greater clarity.

Fig. 13 is a section of another alternate form of the curvilinear rib shown in Fig. 5.

Fig. 14 is a section of another alternate form of the curvilinear rib shown in Fig. 5.

Fig. 15 is a section of another alternate form of the curvilinear rib shown in Fig. 5.

Fig. 16 is a section of another alternate form of the curvilinear rib shown in Fig. 5.

Fig. 17 is a. section of another alternate form of the curvilinear rib shown in Fig. 5.

Fig. 18 is a section of the transverse joint between spaced pairs of preformed strips of the curvilinear rib, such as those in Fig. 17.

The shelter hereinafter to be described may be set up directly on the ground or a minimal substructure may be supplied comprising groundengaging or anchoring means, such as pier, post or block I supporting sill members or floor joist 2 and floor 3. In Fig. 1, floor 3 is shown supporting framework 4 of a superstructure. Floor, sills, joist are herein synonymous with substructure.

Lower ends of parallel rib segments 4a, here five in number, rest on weight-diifusing basefasteners 5 which are fixed to one side of the substructure, and upper ends of the rib segments to are joined in a manner hereinafter described to the upper ends of rib segments 4b which rest on similar weight-diffusing base fasteners fixed to the opposite side of the substructure. Each rib segment is quadrantal lengthwise and thus each butt-joined pair of rib segments 4a and 4b completes a semi-circular rib. The five ribs here so formed may be spaced at the top by crosstie member 6 in a manner similar to that described in the parent patent. Parallel vertical end ribs 1' rest on weight-diffusing base-fasteners 5 and are joined demountably at theupper ends to the outside semi-circular rib in a manner similar to that described in the parent patent.

Fig. 2 illustrates a side view of the shelter frame and Fig. 3, an end view. Since the invention concerns the fitting of sections of the covering, which may have been shipped to the erection site nested in a relatively flat bundle (see Kid d Fig. 4), to the semi-circular ribs 4, the illustrations of the framework may be taken to show also the sections fitted thereto.

The structure at the joint between sections of the covering and the framework is shown in Fig.

5. Rib segments 4a and 41) each comprise two arc-shaped strips formed to be curvilinear both lengthwise and crosswise thereof. These strips 8 and 8' are held fixed in spaced relation by fasr tener 9, here having the form of a shouldered rivet opposite ends of which are caught through strips 8 and 8' to provide a pair of undercut spaced lips it on opposite sides of each segment. Thi provides an aperture, groove 01' slot between lips 10 and extending, in this instance, entirely through the rib segment and from end to the opposite end thereof. Into the slot between lips to, tongues H on a pair of contiguous sections of the covering, such as panels l2, having hook-like folds or flanges I3, are brought into engagement with lips l0; thereupon longitudinally extending fastening means M having a cross section both solid and rigid and comprising a driving head i5, and a concave waist i6 and a taper tip ii is entered into the slot between entered tongues i l and from the side of the slot, taper tip ll being narrower than the slot. Force is then applied on head 15 to cause fastening means ('4 to enter the slot and simultaneously to be bent lengthwise to conform to the arc-shaped contours of the rib segment both inside and outside the slot. Shoulder 18 on fastening means I4 i then effectively caught in the hollow interior of the rib segment by the undercut lips of the slot wherein flanges 13 are held against withdrawal from the slot and sections (2 are fastened firmly to the framework.

Insulation material in sheet form may be loosely positioned between opposite inner faces of the double wall thus formed, or insulation material [9 may be bonded to opposite inner wall faces 20 in such manner as to leave voids 2i between faces 20. Where insulation material is bonded directly to face 20 of the outer weather facing 22, other voids 2! may first be provided between insulation 19 and inner face 28 to provide for the condensation of moisture otherwise trapped in the wall and the voiding of condone sate from the wall. The rebated portions 23 of sections or panels [2 fit the arc-shaped contours of rib segment to or M)- both lengthwise and crosswise of the segment. Tongues Il may comprise the covering itself or constitute flanges on the covering and the marginal extremities or hooklike folds 13 may be thickened as at 24 by folding, extrusion, molding, crimping, knurling, upsetting or the like to provide a shoulder resisting lateral stress otherwise tending to pull tongues H from engagement with the undercut under lips 10. Fastening mean 14 preferably has a rigid cross section and may be made of deformed metal wire, extruded metal or plastics. Or as I have shown in another place it may be given a flexible cross section and be made of rubber, asphalted fiber or the like. The cross section of strips 8, 8 may be rigid or tiflly resilient. The loops engaging lips it may be rigid or stifiiy resilient. Since the entered cross-sectional bulge 25 of fastening means [4 is wider than the normal width of slot entered, lateral entrance of bulge 25 requires a temporary change of dimension of one of the three different elements being joined.

-Thus, one of the strips 8, 8 may be of heattreated carbon steel having sufiicient resilience to permit the slot between lips 10 to be temporarily widened as bulge 25 passes through lips l and into undercut parts 26 of the rib segment.

It is a pertinent feature of the invention that of the three different kinds of elements joined, covering, stiffening and fastening means, any one of the three may have a resilient cross section or any one may have a Wholly rigid cross section. In most instances herein illustrated, one of the three elements has a resilient cross section subject to temporary change of dimension. Other instances are shown and hereinafter described wherein none of the three elements need be provided with a resilient cross section.

In Fig. 6, the two strips 8 and 8' are differently shaped and are then fastened side by ide, as by being spot-welded at 21, to provide spaced pairs of lips ID on opposite sides of the rib segment. Into the undercuts under these lips, tongues ll of an outer covering and an inner covering are fastened in the manner described.

In Fig. 7, the two strips 8 and 8' are similar as to form and differ from the strips in Fig. in that the arc-shaped strips are brought into contact at midpart 28 of each strip and fixed together by rivet 29. If strip 8 is made of heattreated carbon steel, marginal lip l0 may be resiliently flexed relative to strip 8 to permit temporary change of dimension of slot between lips ll] whereby fastening means I4 is driven,

as with a hammer, into the slot between tongues ll. Both strips 8 and 8' may be of ordinary steel and fastened as in Fig. 13 with a resilient -spacer or washer between hard rigid washer 3| held by grommet 32 which permits a slight resilient movement of one trip relative to the other and thus a slight temporary widening of slot between lips l0. Internal parts of panel [2 are provided with tongues 33 which fits into the concave contours 34 of strip 8 or 8' and is held against sidewise movement relative thereto.

In the parent patent, a shelter was described which was especially adapted for use both in very hot and in very cold regions. In both extremes, the matter of proper ventilation is one vital both to health and to comfort, and means were shown but not claimed for securing a maximum degree of effective ventilation on the semi-circular sides of the shelter while keeping out the weather. Openings 35 near floor and top openings 36 in the outer covering may be provided with shields or closures 31 and 38. Intermediate between top and bottom openings are openings 39 between parallel upright ribs and provided with dormer-like shields 40 which are extensions of roof covering IZ. These many openings in addition to door 41, windows or screened openings 42 and ventilator 43 in opposite semicircular ends of the "Q hut make it possible to secure a maximum flow of air into and spent air from the space enclosed (in the direction of the arrows in Fig. 8). The principle of ensuring entrance of large amounts of fresh air at the floorline supplies a quality of ventilation that particularly adapts a metal-faced shelter of the type described for comfortable use in regions of tropical heat and humidity.

Figure 9 shows the general character of the joint between the covering and framework of the superstructure and the substructure, rib segment 41) of the framework 4 resting at the lower end on weight-diffusing fastener 5 fixed to substructure 3 by screw 44 and to the framework by screw 45. Under the lower margins of the roof covering, channel 45 drained by ducts 41' permits moisture condensed in the wall or otherwise admitted therewithin to run downward face 20 or via voids 2|, 2 I and then from the superstructure and substructure. Upward opening closure 31 is fastened at 48 to the roof covering.

Fig. 10 shows a pair of contiguous panels HA and IZB having a common weather-facing 22 which, in this instance, is of sufficiently resilient material to have a hinge-like loop 49 entered between lips in of stiffener 50 whereupon fastening means I4 is driven into the slot between lips 10 from the side of the slot to complete the joint. Fig. 4 shows four such panels comprising slabs of semi-rigid insulation material nested compactly for shipment in a relatively flat bundle but capable of being warped to the semicircular framework 4 and fastened thereto in the manner described whereupon fastening means l4 makes the seam between contiguous panels continuously tight from upper to lower extremities thereof. It is to be noted that the rib itself in this instance is of the type preferred in the parent patent.

In Fig. 11, the manner of holding rib segment 4a firmly butt-joined to rib segment 4b is shown in transverse section and in perspective from the side in Fig. 12: strips 8 and 8 being separated by spacer 5| and screw fasteners 52 pass through strips 8, 8 and through side plates 53 which lap an opposite sides of both rib segments. This coupling holds the quadrantal rib segments fixedly joined while leaving continuously open the grooves and the undercut lips on opposite sides of the rib, these grooves or slots and undercuts extending continuously from opposite ends of the rib from sill to opposite sill through the coupling members and the housing for the slots being compound curved from sill to sill.

Alternate stiffening members and joining means shown in Figures 13-17 comprise elements curvilinear both in transverse and longitudinal sections, such as rib segments 4a and 4b, or they may comprise elements curvilinear only in crosssection, such as end ribs 1.

In Fig. 13, strips 8 and 8' adjacent lips l0 have a cross section resembling the structure shown in Fig. '7, except that intermediate transverse parts of strips 8, 8' are formed to have several oppositely posiitoned ridges 5:; held in resilient spaced relation by grommet 32 having an inner shoulder and the clinched head holding resilient washer is as previously described. The structure is such that the space between oppositely positioned ridges 54 is less than the greater diameter of fastening means 56 which is provided with concavities 5? into which ridges 54 fit; Sections 58 of a covering in sheet form, such as plywood, gypsumboard, fiberboard, insulation board and the like may be applied in lapped relation as shown and fastened by force applied to drive fastening means 55 into the slot between strips 8 and 8 against the resilient resistance of washer 39 which will be compressed to permit entrance of parts of fastening means 56 wider than narrower parts of the slot which will expand to hold concavities 5's caught in ridges 54. Resilient washer 38 may be dispensed. with, grommet 32 being spaced lengthwise of strips 8 and 8 from similar grommets (not shown), at such intervals as to permit the slot to be temporarily widened within the elastic limits of the metal constituting strips ii and 8 between the spaced grommets. On the opposite face of the rib shown in Fig. 13, tongues H are caught in the slot between lips it by fastening means 54 entered from the side of the slot in the manner described.

Entered parts of tongues H may be notched inwardly at intervals from the marginal parts thereof in a manner old in the art and not here shown, to ease the warping or bending of the tongues to the lengthwis curvature of lips I0. It is apparent from the drawing that either type of fastening means may be entered from either side of the rib, or a single type may be utilized on both sides of th rib,

In Fig. 14, ridges 54' are not directly opposite one another but alternate in such a manner as to be coactive with fastener 59 in which the concavity 51' is a lengthwise spiral as in a screw and fastening means has a screw head 60. Strips '8, 8 may be held in resilient spaced relation as by grommets 32 spaced intermittently of the "strips as in the structure shown in Fig. 13, in

which case fastener 59 may both be driven and screwed. Or strips 8, 8' may be held in fixed spaced relation without resilient washer 3'0 and by means hereinafter described. Fastener 59 may be entered into the rib with equal effectiveness from either side of the slot and from either side of framework d and fastener '14 may be entered to hold tongues H in the slot between lips it on either side of framework 4.

In Fig. 15, lengthwise grooves Si are provided for one or more nail receiving and gripping elements 62. This element may be of wood or comprise fibrous material impregnated with pitch,

asphalt or the like into which gritty or frictional substance is mixed prior to extrusion or formation into a ropelike strand. Element 62 is held between strips 8 and B by rivets 53. An ordinary nail or one coated with frictional material may be driven through the side of receiving and spacing element 52 from either side of the framework '6 and be held securely against easy withdrawal therefrom.

In Fig. 16, the sides 65 of strips 8 and 8 are held fixedly spaced at a distance nearly double the diameter of the double-headed nail 66 and lengthwise ridge 54" on one strip is positioned so as to alternate with ridges fi i' on the other strip whereby a nail driven therebetween is deflect-ed first in one direction and then in another. This bends fastening means 66 lengthwise in th slot between strips 8, 8' and between parts of the strips which are non-parallel and provides a shoulder which is coactive with one of the ridges 54 to be highly resistant to withdrawal. Fastening means I4 may be driven into the slot between lips I!) on the opposite side of the rib and where the lengthwise axis of this rib is curvilinear, fastening means it is bent lengthwise to conform with the contours of lips 10, whereupon shoulder 88 is caught in the undercut 89 under lip ID. Either fastening means, 66 or M, may be used on either side of framework 4 to fasten sections of the covering to segments of the framework.

In Fig. 17, strips 8 and 8 are preformed to have a channel-like cross section except that lips are provided with undercuts 69. The metal transversely rectilinear sides 65 of strips 8 and 8' are fixedly spaced to barely receive nail 64 and prior to being laterally fixed in spaced relation are coated with a composition having a slightly resilient and/or frictional character of such thickness that nail lid driven from either side of framework 4 into the slot between strips 8 and 8' will be caught and frictionally held between faces it of the frictional composition, while faces 10 are held spaced at a distance slightly less than the diameter of nail S4. Fastening means I4 ,holds tongues H firmly fixed in undercuts B9.

It is to be noted that in the various types of ribs here discussed, many have slot openings on opposite sides of the rib substantially wider than the midpart of the slot. This permits sheet material to be lapped over the slot (which hides the slot) and nails to be more easily entered into the hidden slot than would be possible if the slot openings were as narrow as the fastening means entered into them.

In Figures i l, 15 and 17, means holding strips 8 and 8 in fixed spaced relation are not shown. Fig. 18 iilustrates one such means. The walls of strips 8 and 8 are brought into contact as at 'H only at intervals lengthwise of the strips and in the immediate vicinity of the means holding the strips in fixed relation, here the grommet 12. The exact method of holding strips 8 and 8 in either fixed or resilient spaced relation is not intended to be limited to the examples herein illustrated but may be varied to include other means, such, as for for example, that wherein grommet 22 itself comprises a stiiily resilient material.

Moreover, the description of the sections of the covering being compactly nested in a relatively flat bundle is not intended to be limited to wholly fiat sheet materials, slabs or panels. Corrugated metal be nested in a relatively compact bundle. Nor is it imperative that the shelter herein described be limited to one covered by material shippable in a fiat bundle. What has been described is a shelter that is quickly erected from preformed parts which are compactly transported in knockdown. Corrugated metal, wherein the lengthwise axis of each corrugation is curvilinear, may be utilized as the covering of the shelter herein described. What is significant in the design is that a wide variety of covering materials in sheet form may be employed to provide the structure, stiffened and joined as described and, in the preferred form, the invention makes possible the wide use of sheet materials compactly nested for shipment and warped to the curvilinear ribs in the process of erection.

The method of erection of the shelter according to the invention is as follows: A substructure is provided having a floor supported on groundengaging means or comprising supported parallel sill members. Segments of a skeleton framework, including ribs of butt-joined quadrantal segments, are attached by means of load-diffusing base-connectors to the substructure. The ribs are positioned parallel and upright and sections of the covering are unnested and adjusted to conform to the curved contours of the ribs. The fastening means used to unite covering and framework each has a drivinghead to receive and a taper tip to transmit force applied to cause said means to enter the rib from the side thereof by means of a lengthwise slot therein and to be bent lengthwise simultaneously to conform to the curvilinear contours of the rib adjacent the slot, whereupon an entered shoulder or frictional means resists withdrawal and tends to hold covering and framework securely united. After the roof ribs and roof covering are united, the end ribs, here shown to be rectilinear, are set up, the end covering is applied and the structure thus achieved is strong enough to resist heavy winds and snow loads and to remain rigid and highly insulative and resistant to harm from moisture both from within and without.

The insulation used between inner and outer sheets of the covering may be even more varied than as yet described. This insulation may be either in sheet or blanket form. It may comprise terial, moisture tending to be drawn from the interior into the wall structure, is removed from the structure automatically by means of the voids provided between the metal or highly heat conductive outer weather facing and the contiguous insulation material and by drainage means provided at the bottom ends of those voids.

In tests made on the structure herein described, the fastening means joiningcovering to frame was formed of heavy wire stock drawn through a die and it is a virtue of the invention that the fastening means may be shipped in coils and bent to conform to the curvature of the slotted segment by the same force that drives the entered taper tip thereinto. It is to be noted that immediately next the taper tip, the solid rigid cross section of the fastener comprises a bulge wider than normal entrance into the slot. Force exerted by applying a hammer to the head of the fastener causes the taper to push progressively outward on the lips of the slot to widen the slot. This Widening must be temporary which means within the elastic limits of the metal and stored up energy in the metal causes the lips of the slot to snap back after the bulge has passed through and to hold the bulge snugly therewithin. lhis is only possible where the radius of lengthwise curvature of the rib segment is relatively long (above in the tested structure) as otherwise the forcing of the bulge through the narrower slot would permanently deform the metal housin the slot and prevent the completion of the joint described. In tests, the joint here described resisted a pull of 156 lbs. per lineal inch of slot. This strength plus that insured by the secure butt-joining of the rib segments is essential to resist the effects of high wind pressures encountered where this type of shelter is commonly used: i. e., in the hurricane belt. The safety of those occupying such a shelter was of primary concern in the tests run on the structure described, and the strength achieved was found adequate to insure that safety.

Demounting of the shelter is done by reversing the erection procedure. Since fastening means it does not require that the metal weather-facing be punctured, the rusting common around nailholes through metal subjected to exterior exposure is avoided, together with the consequent enlargement of the puncture, consequent leaking, the decrease in effectiveness of the in sulation, and subsequent rapid disintegration of the structure. This makes salvage after a considerable period of use practically 166 per cent.

it will be understood that any of the variants and modifications in the parts essential to providingthe demountable shelter in the manner described may be used separately and in any desired combination,

The drawings, being illustrative only, are more or less diagrammatic in character and it is observed that various minor changes, as in the substructure, for example, or in the butt-connectors, or in other parts of the insulated shelter herein illustrated may be made without departing from the spirit and scope of the invention as set forth in the appended claims.

Having thus fully described my invention, its utility and mode of fabrication, compact transport, erection, manner of ventilation, and disassembly, what I claim and desire to secure by Letters Patent of the United States is:

1. In a housing of the sheet-covered frame type, a frame member made up of a plurality of longitudinally curved segments, each formed of a .pair of metallic channels of similar cross section secured together side to side in spaced relation with opposing longitudinal margins parallel to form openings continuous along opposite lengthwise curved sides of the segment, and means to butt-join said segments to provide uninterrupted continuous openings into hollows extending centrally crosswise between said channels, said means comprising coupling elements interposed between said channels across meeting ends of butted segments and fasteners transfixing said segments and interposed coupling elements diametrically substantially normal to a plane passing through said opposed continuous openings, said frame member covered by and between sheets fixed face to face to said opposite curved sides by fastening means passed through said continuous openings into said hollows.

2. In a housing of the sheet-covered metallic frame type, a frame member made up of a plurality of longitudinally curved segments, each formed of a pair of metallic channels having Y curvilinear cross section and joined intermittently together side to side with opposing longitudinal margins parallel to form openings into the hollow central interior of the segment from opposite lengthwise curved sides thereof, and means to butt-join said segments to provide uninterrupted continuous openings and comprising a stiffener block interposed between said channels across meeting ends of butted segments and fasteners transfixing said segments and interposed block diametrically substantially normal to a plane passing through said continuous openings, said continuous openings aligned across said meeting ends to receive therethrough metallic fastening means for sheets of a double covering fixed face to face against said lengthwise curved sides.

3. The housing frame as defined in claim 1 wherein said pair of channels are secured together side to side by spacing fasteners piercing the sides of the channels intermittently lengthwise of the segments.

4. In a housing of the covered frame type, a frame member comprising butt-joined curvilinear segments, each consisting of metallic strips fashioned concavely in cross section and secured intermittently lengthwise in fixed relation side to side with opposing margins parallel to form continuous slots along opposite sides and inwardly opening into an inmost hollow, and means to fasten the segments end to end comprising common tie members interiorly and exteriorly of the channels lying across adjoining ends of the segments and means transfixing said segments and tie members to lock the same together without interrupting access through said slots into said hollow.

5. In a housing of the covered frame type, a frame member made up of a plurality of segments, each continuously curved lengthwise from end to end to a single radius and formed of metallic channels joined intermittently lengthwise side to side with opposing longitudinal margins parallel to provide continuous openings along the segments and into the lengthwise curved sides thereof, and means to butt-join said segments to provide uninterrupted continuous openings into innermost hollows of the segments in meeting ends thereof, comprising a rectangular stiffener block narrower in one sectional dimension than the width of said channels and wider in another sectional dimension than the combined depths of said channels interposed between said channels, a pair of elements overlapping said butted segments exteriorly thereof and free of the slots therein, and fastening means transfixing said sections, said elements and said interposed block through its widest sectional dimension normal to a plane passing through said opposed continuous openings, said frame member covered by and supporting the weight of covering sheets fixed to said curved sides by mechanical fasteners entered through said openings and into said hollows in said meeting ends.

6. In a housing of the metal frame and sheet covering type, parallel upright covered frame members each made up of a plurality of endbutted hollow segments comprising metallic strips curved both lengthwise and crosswise in compound curvature and having along the lengthwise curved sides of the segments continuous slotlike openings the length of the segments and inwardly extending into centrally crosswise hollow interiors thereof, butt-joining means comprising coupling members overlapping the butted segments on opposite sides of meeting ends thereof and rigid fasteners piercing the lapped mem bers to rigidly hold the butted segments to a common radius of lengthwise curvature and to permit uninterrupted lateral entrance through said continuous slot-like openings of the joined segments into said centrally crosswise hollow interiors', covering sheets curved to said radius and supported on and by said frame members, and

12 pling members spaced from said slots in a pair having sides snugly fitting and overlappin the butted segments on opposite sides of meeting ends thereof, rigid fasteners piercing the segments and said pair, metal covering sheets curved to lie over and to be supported by said frame member, and metal fastening means entering said hollow portions of the frame member through the continuous slots from the sides thereof to hold said sheets securely on said frame member.

CORWIN D. WILLSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 758,642 Gotsche May 3, 1904 963,536- Finlayson et al July 5, 1910 1,230,586 Lister June 19, 1917 1,298,836 Vetter Apr. 1, 1919 1,347,881 Vetter July 27, 1920 1,350,493 Goodrich Aug. 24, 1920 1,351,435 Nissen Aug. 31, 1920 1,359,989 Hiegel Nov. 23, 1920 1,447,191 Vetter Mar. 6, 1923 1,508,338 King Sept. 9, 1924 1,745,588 Shodron Feb. 4, 1930 1,900,541 Buelow et a1 Mar.- 7, 1933 1,949,543 Loucks Mar. 6, 1934 2,071,270 Dellinger Feb. 16, 1937 2,427,937 Willson Sept. 23, 1947 FOREIGN PATENTS Number Country Date 80,357 Switzerland July 16, 1919 308,042 Great Britain Mar. 21, 1929 351,369 Great Britain June 25, 1931 722,241 France 1931 680,848 Germany 1939 579,443 Great Britain 1946 OTHER REFERENCES The Architectural Forum, February 1944, pages 91, 92 and 93. 

